Merge branch 'tipc-diag'

GhantaKrishnamurthy MohanKrishna says:

====================
tipc: socket diagnostics additions for AF_TIPC

The following patchsets add socket diagnostics support for AF_TIPC by
using the sock diag framework. The patchset was created on top of
commit id: fb66cb0.

New iproute2 package is needed to use this functionality which will
be sent for review in a seperate mail.

The commit series improves diagnosis of tipc sockets by exporting the
configuration, states and statistics of sockets.

The series has been co-authored by Parthasarathy Bhuvaragan and
consist of two parts:

1-2:  Adaptations of existing code to support sock_diag framework.
We modify existing functions to support socket diagnostics. Required
information about the sockets are exported.

3:  Step sk_drops during packet drop.
This occurs if the packet cannot be queued due to queue length exceeding
configured thresholds.

The diag module is optional, and if enabled it will be loaded on demand
when needed.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/tipc_netlink.h

@@ -114,6 +114,13 @@ enum {
 	TIPC_NLA_SOCK_REF,		/* u32 */
 	TIPC_NLA_SOCK_CON,		/* nest */
 	TIPC_NLA_SOCK_HAS_PUBL,		/* flag */
+	TIPC_NLA_SOCK_STAT,		/* nest */
+	TIPC_NLA_SOCK_TYPE,		/* u32 */
+	TIPC_NLA_SOCK_INO,		/* u32 */
+	TIPC_NLA_SOCK_UID,		/* u32 */
+	TIPC_NLA_SOCK_TIPC_STATE,	/* u32 */
+	TIPC_NLA_SOCK_COOKIE,		/* u64 */
+	TIPC_NLA_SOCK_PAD,		/* flag */
 
 	__TIPC_NLA_SOCK_MAX,
 	TIPC_NLA_SOCK_MAX = __TIPC_NLA_SOCK_MAX - 1
@@ -238,6 +245,18 @@ enum {
 	TIPC_NLA_CON_MAX = __TIPC_NLA_CON_MAX - 1
 };
 
+/* Nest, socket statistics info */
+enum {
+	TIPC_NLA_SOCK_STAT_RCVQ,	/* u32 */
+	TIPC_NLA_SOCK_STAT_SENDQ,	/* u32 */
+	TIPC_NLA_SOCK_STAT_LINK_CONG,	/* flag */
+	TIPC_NLA_SOCK_STAT_CONN_CONG,	/* flag */
+	TIPC_NLA_SOCK_STAT_DROP,	/* u32 */
+
+	__TIPC_NLA_SOCK_STAT_MAX,
+	TIPC_NLA_SOCK_STAT_MAX = __TIPC_NLA_SOCK_STAT_MAX - 1
+};
+
 /* Nest, link propreties. Valid for link, media and bearer */
 enum {
 	TIPC_NLA_PROP_UNSPEC,

include/uapi/linux/tipc_sockets_diag.h

@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* AF_TIPC sock_diag interface for querying open sockets */
+
+#ifndef _UAPI__TIPC_SOCKETS_DIAG_H__
+#define _UAPI__TIPC_SOCKETS_DIAG_H__
+
+#include <linux/types.h>
+#include <linux/sock_diag.h>
+
+/* Request */
+struct tipc_sock_diag_req {
+	__u8	sdiag_family;	/* must be AF_TIPC */
+	__u8	sdiag_protocol;	/* must be 0 */
+	__u16	pad;		/* must be 0 */
+	__u32	tidiag_states;	/* query*/
+};
+#endif /* _UAPI__TIPC_SOCKETS_DIAG_H__ */

net/tipc/Kconfig

@@ -34,3 +34,11 @@ config TIPC_MEDIA_UDP
 	  Saying Y here will enable support for running TIPC over IP/UDP
 	bool
 	default y
+
+config TIPC_DIAG
+	tristate "TIPC: socket monitoring interface"
+	depends on TIPC
+	default y
+	---help---
+	Support for TIPC socket monitoring interface used by ss tool.
+	If unsure, say Y.

net/tipc/Makefile

@@ -14,3 +14,8 @@ tipc-y	+= addr.o bcast.o bearer.o \
 tipc-$(CONFIG_TIPC_MEDIA_UDP)	+= udp_media.o
 tipc-$(CONFIG_TIPC_MEDIA_IB)	+= ib_media.o
 tipc-$(CONFIG_SYSCTL)		+= sysctl.o
+
+
+obj-$(CONFIG_TIPC_DIAG)	+= diag.o
+
+tipc_diag-y	:= diag.o

net/tipc/diag.c

@@ -0,0 +1,114 @@
+/*
+ * net/tipc/diag.c: TIPC socket diag
+ *
+ * Copyright (c) 2018, Ericsson AB
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "ASIS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "core.h"
+#include "socket.h"
+#include <linux/sock_diag.h>
+#include <linux/tipc_sockets_diag.h>
+
+static u64 __tipc_diag_gen_cookie(struct sock *sk)
+{
+	u32 res[2];
+
+	sock_diag_save_cookie(sk, res);
+	return *((u64 *)res);
+}
+
+static int __tipc_add_sock_diag(struct sk_buff *skb,
+				struct netlink_callback *cb,
+				struct tipc_sock *tsk)
+{
+	struct tipc_sock_diag_req *req = nlmsg_data(cb->nlh);
+	struct nlmsghdr *nlh;
+	int err;
+
+	nlh = nlmsg_put_answer(skb, cb, SOCK_DIAG_BY_FAMILY, 0,
+			       NLM_F_MULTI);
+	if (!nlh)
+		return -EMSGSIZE;
+
+	err = tipc_sk_fill_sock_diag(skb, tsk, req->tidiag_states,
+				     __tipc_diag_gen_cookie);
+	if (err)
+		return err;
+
+	nlmsg_end(skb, nlh);
+	return 0;
+}
+
+static int tipc_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	return tipc_nl_sk_walk(skb, cb, __tipc_add_sock_diag);
+}
+
+static int tipc_sock_diag_handler_dump(struct sk_buff *skb,
+				       struct nlmsghdr *h)
+{
+	int hdrlen = sizeof(struct tipc_sock_diag_req);
+	struct net *net = sock_net(skb->sk);
+
+	if (nlmsg_len(h) < hdrlen)
+		return -EINVAL;
+
+	if (h->nlmsg_flags & NLM_F_DUMP) {
+		struct netlink_dump_control c = {
+			.dump = tipc_diag_dump,
+		};
+		netlink_dump_start(net->diag_nlsk, skb, h, &c);
+		return 0;
+	}
+	return -EOPNOTSUPP;
+}
+
+static const struct sock_diag_handler tipc_sock_diag_handler = {
+	.family = AF_TIPC,
+	.dump = tipc_sock_diag_handler_dump,
+};
+
+static int __init tipc_diag_init(void)
+{
+	return sock_diag_register(&tipc_sock_diag_handler);
+}
+
+static void __exit tipc_diag_exit(void)
+{
+	sock_diag_unregister(&tipc_sock_diag_handler);
+}
+
+module_init(tipc_diag_init);
+module_exit(tipc_diag_exit);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, AF_TIPC);

net/tipc/socket.c

@@ -2122,8 +2122,10 @@ static void tipc_sk_filter_rcv(struct sock *sk, struct sk_buff *skb,
 		    (!sk_conn && msg_connected(hdr)) ||
 		    (!grp && msg_in_group(hdr)))
 			err = TIPC_ERR_NO_PORT;
-		else if (sk_rmem_alloc_get(sk) + skb->truesize >= limit)
+		else if (sk_rmem_alloc_get(sk) + skb->truesize >= limit) {
+			atomic_inc(&sk->sk_drops);
 			err = TIPC_ERR_OVERLOAD;
+		}
 
 		if (unlikely(err)) {
 			tipc_skb_reject(net, err, skb, xmitq);
@@ -2202,6 +2204,7 @@ static void tipc_sk_enqueue(struct sk_buff_head *inputq, struct sock *sk,
 
 		/* Overload => reject message back to sender */
 		onode = tipc_own_addr(sock_net(sk));
+		atomic_inc(&sk->sk_drops);
 		if (tipc_msg_reverse(onode, &skb, TIPC_ERR_OVERLOAD))
 			__skb_queue_tail(xmitq, skb);
 		break;
@@ -3160,16 +3163,33 @@ msg_full:
 	return -EMSGSIZE;
 }
 
+static int __tipc_nl_add_sk_info(struct sk_buff *skb, struct tipc_sock
+			  *tsk)
+{
+	struct net *net = sock_net(skb->sk);
+	struct tipc_net *tn = tipc_net(net);
+	struct sock *sk = &tsk->sk;
+
+	if (nla_put_u32(skb, TIPC_NLA_SOCK_REF, tsk->portid) ||
+	    nla_put_u32(skb, TIPC_NLA_SOCK_ADDR, tn->own_addr))
+		return -EMSGSIZE;
+
+	if (tipc_sk_connected(sk)) {
+		if (__tipc_nl_add_sk_con(skb, tsk))
+			return -EMSGSIZE;
+	} else if (!list_empty(&tsk->publications)) {
+		if (nla_put_flag(skb, TIPC_NLA_SOCK_HAS_PUBL))
+			return -EMSGSIZE;
+	}
+	return 0;
+}
+
 /* Caller should hold socket lock for the passed tipc socket. */
 static int __tipc_nl_add_sk(struct sk_buff *skb, struct netlink_callback *cb,
 			    struct tipc_sock *tsk)
 {
-	int err;
-	void *hdr;
 	struct nlattr *attrs;
-	struct net *net = sock_net(skb->sk);
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct sock *sk = &tsk->sk;
+	void *hdr;
 
 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_SOCK_GET);
@@ -3179,19 +3199,10 @@ static int __tipc_nl_add_sk(struct sk_buff *skb, struct netlink_callback *cb,
 	attrs = nla_nest_start(skb, TIPC_NLA_SOCK);
 	if (!attrs)
 		goto genlmsg_cancel;
-	if (nla_put_u32(skb, TIPC_NLA_SOCK_REF, tsk->portid))
-		goto attr_msg_cancel;
-	if (nla_put_u32(skb, TIPC_NLA_SOCK_ADDR, tn->own_addr))
+
+	if (__tipc_nl_add_sk_info(skb, tsk))
 		goto attr_msg_cancel;
 
-	if (tipc_sk_connected(sk)) {
-		err = __tipc_nl_add_sk_con(skb, tsk);
-		if (err)
-			goto attr_msg_cancel;
-	} else if (!list_empty(&tsk->publications)) {
-		if (nla_put_flag(skb, TIPC_NLA_SOCK_HAS_PUBL))
-			goto attr_msg_cancel;
-	}
 	nla_nest_end(skb, attrs);
 	genlmsg_end(skb, hdr);
 
@@ -3205,16 +3216,19 @@ msg_cancel:
 	return -EMSGSIZE;
 }
 
-int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
+int tipc_nl_sk_walk(struct sk_buff *skb, struct netlink_callback *cb,
+		    int (*skb_handler)(struct sk_buff *skb,
+				       struct netlink_callback *cb,
+				       struct tipc_sock *tsk))
 {
-	int err;
-	struct tipc_sock *tsk;
-	const struct bucket_table *tbl;
-	struct rhash_head *pos;
 	struct net *net = sock_net(skb->sk);
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	u32 tbl_id = cb->args[0];
+	struct tipc_net *tn = tipc_net(net);
+	const struct bucket_table *tbl;
 	u32 prev_portid = cb->args[1];
+	u32 tbl_id = cb->args[0];
+	struct rhash_head *pos;
+	struct tipc_sock *tsk;
+	int err;
 
 	rcu_read_lock();
 	tbl = rht_dereference_rcu((&tn->sk_rht)->tbl, &tn->sk_rht);
@@ -3226,12 +3240,13 @@ int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
 				continue;
 			}
 
-			err = __tipc_nl_add_sk(skb, cb, tsk);
+			err = skb_handler(skb, cb, tsk);
 			if (err) {
 				prev_portid = tsk->portid;
 				spin_unlock_bh(&tsk->sk.sk_lock.slock);
 				goto out;
 			}
+
 			prev_portid = 0;
 			spin_unlock_bh(&tsk->sk.sk_lock.slock);
 		}
@@ -3243,6 +3258,75 @@ out:
 
 	return skb->len;
 }
+EXPORT_SYMBOL(tipc_nl_sk_walk);
+
+int tipc_sk_fill_sock_diag(struct sk_buff *skb, struct tipc_sock *tsk,
+			   u32 sk_filter_state,
+			   u64 (*tipc_diag_gen_cookie)(struct sock *sk))
+{
+	struct sock *sk = &tsk->sk;
+	struct nlattr *attrs;
+	struct nlattr *stat;
+
+	/*filter response w.r.t sk_state*/
+	if (!(sk_filter_state & (1 << sk->sk_state)))
+		return 0;
+
+	attrs = nla_nest_start(skb, TIPC_NLA_SOCK);
+	if (!attrs)
+		goto msg_cancel;
+
+	if (__tipc_nl_add_sk_info(skb, tsk))
+		goto attr_msg_cancel;
+
+	if (nla_put_u32(skb, TIPC_NLA_SOCK_TYPE, (u32)sk->sk_type) ||
+	    nla_put_u32(skb, TIPC_NLA_SOCK_TIPC_STATE, (u32)sk->sk_state) ||
+	    nla_put_u32(skb, TIPC_NLA_SOCK_INO, sock_i_ino(sk)) ||
+	    nla_put_u32(skb, TIPC_NLA_SOCK_UID,
+			from_kuid_munged(sk_user_ns(sk), sock_i_uid(sk))) ||
+	    nla_put_u64_64bit(skb, TIPC_NLA_SOCK_COOKIE,
+			      tipc_diag_gen_cookie(sk),
+			      TIPC_NLA_SOCK_PAD))
+		goto attr_msg_cancel;
+
+	stat = nla_nest_start(skb, TIPC_NLA_SOCK_STAT);
+	if (!stat)
+		goto attr_msg_cancel;
+
+	if (nla_put_u32(skb, TIPC_NLA_SOCK_STAT_RCVQ,
+			skb_queue_len(&sk->sk_receive_queue)) ||
+	    nla_put_u32(skb, TIPC_NLA_SOCK_STAT_SENDQ,
+			skb_queue_len(&sk->sk_write_queue)) ||
+	    nla_put_u32(skb, TIPC_NLA_SOCK_STAT_DROP,
+			atomic_read(&sk->sk_drops)))
+		goto stat_msg_cancel;
+
+	if (tsk->cong_link_cnt &&
+	    nla_put_flag(skb, TIPC_NLA_SOCK_STAT_LINK_CONG))
+		goto stat_msg_cancel;
+
+	if (tsk_conn_cong(tsk) &&
+	    nla_put_flag(skb, TIPC_NLA_SOCK_STAT_CONN_CONG))
+		goto stat_msg_cancel;
+
+	nla_nest_end(skb, stat);
+	nla_nest_end(skb, attrs);
+
+	return 0;
+
+stat_msg_cancel:
+	nla_nest_cancel(skb, stat);
+attr_msg_cancel:
+	nla_nest_cancel(skb, attrs);
+msg_cancel:
+	return -EMSGSIZE;
+}
+EXPORT_SYMBOL(tipc_sk_fill_sock_diag);
+
+int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	return tipc_nl_sk_walk(skb, cb, __tipc_nl_add_sk);
+}
 
 /* Caller should hold socket lock for the passed tipc socket. */
 static int __tipc_nl_add_sk_publ(struct sk_buff *skb,

net/tipc/socket.h

@@ -49,6 +49,8 @@
 #define RCVBUF_DEF  (FLOWCTL_BLK_SZ * 1024 * 2)
 #define RCVBUF_MAX  (FLOWCTL_BLK_SZ * 1024 * 16)
 
+struct tipc_sock;
+
 int tipc_socket_init(void);
 void tipc_socket_stop(void);
 void tipc_sk_rcv(struct net *net, struct sk_buff_head *inputq);
@@ -59,5 +61,11 @@ int tipc_sk_rht_init(struct net *net);
 void tipc_sk_rht_destroy(struct net *net);
 int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb);
 int tipc_nl_publ_dump(struct sk_buff *skb, struct netlink_callback *cb);
-
+int tipc_sk_fill_sock_diag(struct sk_buff *skb, struct tipc_sock *tsk,
+			   u32 sk_filter_state,
+			   u64 (*tipc_diag_gen_cookie)(struct sock *sk));
+int tipc_nl_sk_walk(struct sk_buff *skb, struct netlink_callback *cb,
+		    int (*skb_handler)(struct sk_buff *skb,
+				       struct netlink_callback *cb,
+				       struct tipc_sock *tsk));
 #endif